Hey hey good to see ya still around the place Nath. Hope all is well with you and the family.
Those clamps are production line torque snap off set up. Clamp goes on, torqued up. Snaps off the cup. Next car please.
Do as nath said and you'll find the nut underneath.
Just passing through and saw the confusion. Those round bits come off to reveal a normal 7mm hex with a phillips drive. Spray some lube in there then lever them with a screwdriver or wiggle them with pliers like ozy said. When you're done throw it in the bin (the round bit, not the clamp).